The {10(1)over-bar2} non-cozone twin-twin interactions in Mg: A stability and mobility study using 3-D atomistic simulations

Due to easy activation of tensile twinning in Mg, multiple {10 (1) over bar2} twin variants can interact with each other and form twin-twin boundaries over the course of plastic deformation. Previous studies using 2-D settings provide only a partial understanding of these interactions, especially the non-cozone ones. Here, atomistic simulations are used to study the 3-D structural characteristic and evolution of the non-cozone {10 (1) over bar2} twin-twin junctions. The study reveals the existence of new twin-twin boundaries (TTBs) such as TTBBP and TTBK2, formed after the interaction between the basal prismatic and conjugate twin interfaces with the coherent twin boundary. For both non-cozone twin-twin interactions, the {(1) over bar2 (1) over bar2} TTB and its associated twin-twin junctions are found to play a major role in the {10 (1) over bar2} twin's stability and mobility. Specifically, they promote the growth of the 3-D twin in both the normal and forward directions during the interaction and hinder the detwinning process upon unloading. (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study used atomistic simulations to investigate the 3-D structural characteristics and evolution of non-cozone {10 (1) over bar2} twin-twin junctions in magnesium. It discovered new twin-twin boundaries and discussed their impact on twin stability and mobility.